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Well, hello again, and we are going to see now that second layer we have in the second layer the data

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leak, and we have some layers in this layer.

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We have to some layer that is called Mac.

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And as the.

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This is this Lear is more smart than physical and less smarter than network, it is.

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It works with the physical, physical address and error detection.

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And see our Z Acknowledgments backwards frame.

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Heather and Taylor.

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Bridget, what is it?

10
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Well, in this layer, it takes the message from physical than bytes, and it will end in the beginning

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of the the the message of the bytes and the end of the bytes, another message and other messages so

12
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it can be transferred to the network.

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So the network will understand.

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The following concept, by the way, and this in this layer, the the main machines that works in it,

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remember very well bridges or switches.

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But remember, this word is.

17
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And unconsidered is like we said before, Frank.

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No.

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We have in the third layer, as we said, the network.

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How does it how does the network work when we receive the message from the data link?

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The message that it have the main message from physical plus the heather plus the left part.

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It gives the networks the the beginning and least it gives it the direction.

23
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Where does the message should go?

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Is it going on this road or on this road or it's going to be on this way or we are going to see if it's

25
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us?

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It gives it the direction and it means and to deliver a geological address and fragmentation or seek

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within.

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For me, you wrote you.

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And you is major other units and.

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It is in this part that when we receive that, this frame would transfer it to a logical address and

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we call it fragmentation.

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Or a sequence, but we may would call it a.

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A bucket.

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The message that we get from network to transport, which is the second, the fourth layer or the second

35
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layer after, and it's what we call the baggage and the mainly mainly in this part.

36
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Rotors, rotors are the machines that works in this layer.

37
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And we have next the fourth layer, which is transport.

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Transport.

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It receives the budget and transferred to another mission, which is going to add another and another

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the last part, and we are going to call it segment fragment, and we have a fragmentation or sequencing

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of data, reliable delivery, error recovery, flow control and multiplexing.

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And we have airports.

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What is multiplexing?

44
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We are going to see it in the course of advancing the Cisco packet tracer.

45
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The of part.

46
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And now which type of machines or which type of.

47
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Which type of machines that works on this layer we have here ports, what our ports boards are, the

48
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entrance or it can do also the exit.

49
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In a in a in or alter or maybe a switch or maybe a hub is the place where we put the wire or the cable,

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and mainly it is going to be in our course and our G 45 cable.

51
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We have, again, transparent data service and some firewalls.

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There is there is some firewall that works that work in this layer just to have local control.

53
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Yes, indeed we have that.

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And.

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See you for the next three years.